XAT 2012 — QA & DI Question 15
Answer the following question based on the information given below.
Ramya, based in Shanpur, took her car for a 400 km trip to Rampur. She maintained a log of the odometer readings and the amount of petrol she purchased at different petrol pumps at different prices (given below). Her car already had 10 litres of petrol at the start of the journey, and she first purchased petrol at the start of the journey, as given in table below, and she had 5 litres remaining at the end of the journey.
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Her car’s tank-capacity is 35 litres. Petrol costs Rs. 45/- litre in Rampur. What is the minimum amount of money she would need for purchasing petrol for the return trip from Rampur to Shanpur, using the same route? Assume that the mileage of the car remains unchanged throughout the route, and she did not use her car to travel around in Rampur.
Answer & solution
- A
1714
- B
1724
- C
1734
1744
- E
Data insufficient to answer.
Ramya’s car already has 5 litres in the tank.
Her car’s tank capacity is 35 litres.
She can fill a maximum of 30 litres more.
The petrol cost in Rampur is Rs. 45/litre
As the cost of petrol is lower at all the succeeding petrol pumps that come on the way and hence, to minimize the cost, she will fill enough petrol to reach the first pump i.e 150 km.
She already has 5 litres using which she can travel 40 km.
Hence, to travel 110 km, she will need 110/8 = 13.75 litres at the rate of 45 per litre.
On reaching the first petrol pump in the reverse journey, she will fill up enough petrol to reach the second petrol pump as the cost of petrol in the second pump is less than the cost of the first pump.
This distance is 50 km.
Ramya needs 50/8 = 6.25 litres at the rate of Rs. 40/litre.
For the rest of the journey (200 km) she will need 200/8 = 25 litres at the rate of Rs. 35/litre.
Hence the total cost is (13.75 × 45 + 6.25 × 40 + 25 × 35) = 1743.75
Hence, option (d).